1. Field of the Invention
The invention relates to a combined machine in accordance with the preamble to claim 1.
2. History of the Related Art
Combined machines for simultaneous spreading of seed and commercial fertilizer in agriculture are known, e.g. from the U.S. Pat. No. 3,213,812, which illustrates an apparatus with two mutually, relatively fixed outlet nozzles, arranged side by side and at different working depths under the earth surface. One condition for the apparatus is that earth can be led in between the nozzles (see FIG. 5 of the patent specification), i.e. that the apparatus is intended for fields which are worked by ploughing and harrowing, or in some other way. For sowing seed directly into place in the earth, i.e. farming without ploughing it has been necessary to supply fertilizer in a separate pass or on top of the earth. In addition, the combination sowing machines have only been able to place fertilizer between alternate rows of seed.
Another known technique is apparent from SE 130,953, which is an apparatus for use in sowing directly onto unworked ground.